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8 commits

Author SHA1 Message Date
Stephen Warren
93134e18e8 test/py: handle exceptions in console creation
u_boot_console.exec_attach.get_spawn() performs two steps:
1) Spawn a process to communicate with the serial console.
2) Reset the board so that U-Boot starts running from scratch.

Currently, if an exception happens in step (2), no cleanup is performed on
the process created in step (1). That process stays running and may e.g.
hold serial port locks, or simply continue to read data from the serial
port, thus preventing it from reaching any other process that attempts to
read from the same serial port later. While there is error cleanup code in
u_boot_console_base.ensure_spawned(), this is not triggered since the
exception prevents assignment to self.p there, and hence the exception
handler has no object to operate upon in cleanup_spawn().

Solve this by enhancing u_boot_console.exec_attach.get_spawn() to clean
up any objects it has created.

In theory, u_boot_spawn.Spawn's constructor has a similar issue, so fix
this too.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-02-15 20:58:29 +00:00
Stephen Warren
d8926811fd test/py: fix off-by-one error in spawn matching code
A regex match object's .end() value is already the index after the match,
not the index of the last character in the match, so there's no need to
add 1 to point past the match.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
2016-02-09 15:41:19 -07:00
Stephen Warren
89ab841088 test/py: support running sandbox under gdbserver
Implement command--line option --gdbserver COMM, which does two things:

a) Run the sandbox process under gdbserver, using COMM as gdbserver's
   communication channel.

b) Disables all timeouts, so that if U-Boot is halted under the debugger,
   tests don't fail. If the user gives up in the middle of a debugging
   session, they can simply CTRL-C the test script to abort it.

This allows easy debugging of test failures without having to manually
re-create the failure conditions. Usage is:

Window 1:
./test/py/test.py --bd sandbox --gdbserver localhost:1234

Window 2:
gdb ./build-sandbox/u-boot -ex 'target remote localhost:1234'

When using this option, it likely makes sense to use pytest's -k option
to limit the set of tests that are executed.

Simply running U-Boot directly under gdb (rather than gdbserver) was
also considered. However, this was rejected because:

a) gdb's output would then be processed by the test script, and likely
   confuse it causing false failures.

b) pytest by default hides stdout from tests, which would prevent the
   user from interacting with gdb.

   While gdb can be told to redirect the debugee's stdio to a separate
   PTY, this would appear to leave gdb's stdio directed at the test
   scripts and the debugee's stdio directed elsewhere, which is the
   opposite of the desired effect. Perhaps some complicated PTY muxing
   and process hierarchy could invert this. However, the current scheme
   is simple to implement and use, so it doesn't seem worth complicating
   matters.

c) Using gdbserver allows arbitrary debuggers to be used, even those with
   a GUI. If the test scripts invoked the debugger themselves, they'd have
   to know how to execute arbitary applications. While the user could hide
   this all in a wrapper script, this feels like extra complication.

An interesting future idea might be a --gdb-screen option, which could
spawn both U-Boot and gdb separately, and spawn the screen into a newly
created window under screen. Similar options could be envisaged for
creating a new xterm/... too.

--gdbserver  currently only supports sandbox, and not real hardware.
That's primarily because the test hooks are responsible for all aspects of
hardware control, so there's nothing for the test scripts themselves can
do to enable gdbserver on real hardware. We might consider introducing a
separate --disable-timeouts option to support use of debuggers on real
hardware, and having --gdbserver imply that option.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
2016-02-08 10:22:39 -05:00
Stephen Warren
d27f2fc1e1 test/py: run sandbox in source directory
Some unit tests expect the cwd of the sandbox process to be the root
of the source tree. Ensure that requirement is met.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-01-28 21:01:24 -07:00
Stephen Warren
44ac762b14 test/py: fix spawn.expect multiple match handling
Multiple patterns may be passed to spawn.expect(). The pattern which
matches at the earliest position should be designated as the match. This
aspect works correctly. When multiple patterns match at the same position,
priority should be given the the earliest entry in the list of patterns.
This aspect does not work correctly. This patch fixes it.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-01-28 21:01:24 -07:00
Stephen Warren
e8debf394f test/py: use " for docstrings
Python's coding style docs indicate to use " not ' for docstrings.

test/py has other violations of the coding style docs, since the docs
specify a stranger style than I would expect, but nobody has complained
about those yet:-)

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-01-28 21:01:24 -07:00
Stephen Warren
d314e247e1 test/py: fix timeout to be absolute
Currently, Spawn.expect() imposes its timeout solely upon receipt of new
data, not on its overall operation. In theory, this could cause the
timeout not to fire if U-Boot continually generated output that did not
match the expected patterns.

Fix the code to additionally impose a timeout on overall operation, which
is the intended mode of operation.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-01-28 21:01:22 -07:00
Stephen Warren
d201506cca test/py: Implement pytest infrastructure
This tool aims to test U-Boot by executing U-Boot shell commands using the
console interface. A single top-level script exists to execute or attach
to the U-Boot console, run the entire script of tests against it, and
summarize the results. Advantages of this approach are:

- Testing is performed in the same way a user or script would interact
  with U-Boot; there can be no disconnect.
- There is no need to write or embed test-related code into U-Boot itself.
  It is asserted that writing test-related code in Python is simpler and
  more flexible that writing it all in C.
- It is reasonably simple to interact with U-Boot in this way.

A few simple tests are provided as examples. Soon, we should convert as
many as possible of the other tests in test/* and test/cmd_ut.c too.

The hook scripts, relay control utilities, and udev rules I use for my
own HW setup are published at https://github.com/swarren/uboot-test-hooks.

See README.md for more details!

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org> #v3
2016-01-20 19:06:23 -07:00